gallium: Unify reference counting.

The core reference counting code is centralized in p_refcnt.h.

This has some consequences related to struct pipe_buffer:

* The screen member of struct pipe_buffer must be initialized, or
  pipe_buffer_reference() will crash trying to destroy a buffer with reference
  count 0. u_simple_screen takes care of this, but I may have missed some of
  the drivers not using it.
* Except for rare exceptions deep in winsys code, buffers must always be
  allocated via pipe_buffer_create() or via screen->*buffer_create() rather
  than via winsys->*buffer_create().

1 files changed, 3 insertions, 3 deletions

diff --git a/src/gallium/state_trackers/python/st_device.h b/src/gallium/state_trackers/python/st_device.h
index 7cfe6de9f6..0641aff149 100644
--- a/src/gallium/state_trackers/python/st_device.h
+++ b/src/gallium/state_trackers/python/st_device.h
@@ -68,13 +68,13 @@ struct st_context {
 
 
 struct st_device {
+   /* FIXME: we also need to refcount for textures and surfaces... */
+   struct pipe_reference reference;
+
    const struct st_winsys *st_ws; 
 
    struct pipe_screen *real_screen;
    struct pipe_screen *screen;
-   
-   /* FIXME: we also need to refcount for textures and surfaces... */
-   unsigned refcount;
 };